Normally tacky pressure-sensitive adhesive film-backed tapes usually comprise a non-tacky supporting film and an aggressively tacky adhesive layer on one major surface of the film. The expression "film-backed tape" or "filmic tape" refers to tapes in which the backing is of film as distinguished from paper or fabric backed tapes. The tape is usually prepared by a two-step process in which the adhesive is coated on a previously prepared film. The adhesives preferred for this purpose are called rubber-resin adhesives because they consist of a blend of natural or synthetic rubber and tackifier resin. While other resins and additives also may be included, the rubber and tackifier resin are the principal operative ingredients. Conventional rubber-resin adhesives of this type do not adhere satisfactorily to most films and particularly difficult anchorage problems have been encountered with polyolefin and plasticized vinyl film backings. Although the use of thermoplastic-elastomeric block copolymers in the rubber constituent has improved anchorage, special formulations are generally required, and even then high levels of anchorage may not be attainable with some films. This has necessitated the use of primers, materials capable of adhering well to both the backing and the adhesive, as an intermediate layer in order to assure a high level of anchorage of the adhesive to the backing. In addition, inasmuch as tapes are stored in rolls, the adhesive of the tape adheres to the back side of the tape, i.e., the side of the film or tape opposite to that bearing the adhesive, not infrequently adhering very firmly rendering the use of the tape difficult at best. Such undesired adhesion is avoided by use of an interliner or backsizing the film or tape on the back side in a separate backsizing step. Improved tapes of various backing films as well as a more efficient method of producing the tapes is highly desirable.